Two new virus structures have been completed using image processing techniques developed in this laboratory. The high resolution structure of the herpes simplex virus has been determined (with NIDDK and USUHS). In addition, tail fibers of bacteriophage T7 have been analyzed (with NIDDK, NCI, and Brookhaven National Laboratory). These analyses have been successful in part as a result of new software that has been developed for correlation averaging of single particles (with BEIB and NIDDK).